Smart Updates in the Google Play Store was a feature announced along with Android 4.1 Jelly Bean back at Google I/O and Google has now brought the feature over to other Android devices using the Play Store. What Smart Update does is only download the part of the app that has been updated since the previous version instead of re-downloading the entire app all over again. This allows you to save both a lot of time and a lot of data when updating apps. The best part is that it may also work with older versions of the Play Store as it appears to be an update on Google’s servers and not the Play Store.
This is one of the changes happening behind the scenes with the Google Play Store lately and looks like another great addition. I’m sure that this will ease more than a few user’s fears about updating over cellular connectivity and some strain should also be taken off of both carriers and Google themselves.